Aquarium



FIG. 1 is a perspective view taken from the front and right side of an aquarium showing my new design;

FIG. 2 is a perspective view taken from the front and left side thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof; and

FIG. 5 is a right side elevational view thereof. 

The ornamental design for an aquarium, substantially as shown. 